CN1407256A - Tilted variable axial piston device - Google Patents
Tilted variable axial piston device Download PDFInfo
- Publication number
- CN1407256A CN1407256A CN01142966A CN01142966A CN1407256A CN 1407256 A CN1407256 A CN 1407256A CN 01142966 A CN01142966 A CN 01142966A CN 01142966 A CN01142966 A CN 01142966A CN 1407256 A CN1407256 A CN 1407256A
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- China
- Prior art keywords
- piston
- swash plate
- sliding sleeve
- freely
- running shaft
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B27/00—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders
- F04B27/08—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis
- F04B27/0873—Component parts, e.g. sealings; Manufacturing or assembly thereof
- F04B27/0878—Pistons
- F04B27/0886—Piston shoes
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B27/00—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders
- F04B27/08—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis
- F04B27/0804—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block
- F04B27/0808—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block having two or more sets of cylinders or pistons
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B27/00—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders
- F04B27/08—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis
- F04B27/0804—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block
- F04B27/0821—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block component parts, details, e.g. valves, sealings, lubrication
- F04B27/0826—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block component parts, details, e.g. valves, sealings, lubrication particularities in the contacting area between cylinder barrel and valve plate
- F04B27/083—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block component parts, details, e.g. valves, sealings, lubrication particularities in the contacting area between cylinder barrel and valve plate bearing means
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B27/00—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders
- F04B27/08—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis
- F04B27/0804—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block
- F04B27/0821—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block component parts, details, e.g. valves, sealings, lubrication
- F04B27/0852—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block component parts, details, e.g. valves, sealings, lubrication machine housing
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B27/00—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders
- F04B27/08—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis
- F04B27/0804—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block
- F04B27/0821—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block component parts, details, e.g. valves, sealings, lubrication
- F04B27/086—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block component parts, details, e.g. valves, sealings, lubrication swash plate
- F04B27/0865—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block component parts, details, e.g. valves, sealings, lubrication swash plate swash plate bearing means or driving axis bearing means
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Reciprocating Pumps (AREA)
- Hydraulic Motors (AREA)
Abstract
A variable displacement swash plate axial piston device is provided. A universal joint(90) is joined to a shaft(40) to rotate in circumferential direction of the shaft and has bearing outer races(94) joined to ends of extension parts thereof extending to three directions to freely rotate in circumferential directions of the extension parts, and a sliding sleeve 81, which has a joint hole for inserting the joint, is joined to the swash plate 70 to freely slide, and the bearing outer races coupling the position of the sliding sleeve to transfer power in the process that the sliding sleeve slides and rotates along the swash plate. According to the invention, when the piston is freely sliding-rotating on the swash plate as well as reciprocating, the piston will move along the axial line of an oil cylinder 51 in parallel by increasing turning angle of the piston rod which freely rotatablely joins to the sliding sleeve, and in this manner, the inclination angle can be further increased to prolong the stoke of the piston, so as to increase suction flow rate of the liquid and torque of a rotary shaft.
Description
Technical field
The present invention relates to tilted variable axial piston device in heavy equipment and the use of various industrial field, relate to such tilted variable axial piston device in more detail, promptly, to be converted to straight line motion in order rotatablely moving or the straight line motion of piston to be rotated to rotatablely moving, to rotate the rotation angle expansion of the piston rod that is connected freely (when the to-and-fro motion of piston apparatus is done on the rotation one side of doing to slide on the swash plate that has the plane of inclination on one side with sliding sleeve, this slides over and does the rotation of sliding on the swash plate), thus can along the parallel axes identical with the axial direction of oil cylinder do piston motion, owing to be not subjected to the restriction of piston rod rotation angle, can further increase the angle of inclination of swash plate, can prolong the stroke distances of piston thus, increase the torque of fluid suction flow and running shaft.
Background technique
So-called ramp type, be to give running shaft in general with transmission of torque, the rotating disk (title swash plate) that drive is located on the running shaft is that spiral rotation is carried out at the center with the axis of this running shaft, after swash plate fixedly installs, make the cylinder tube rotation that comprises a plurality of oil cylinders that rotate with running shaft, piston rotates while sliding in the plane of inclination of swash plate, and piston moves back and forth.
The function of such tilted variable axial piston device is because of passive and initiatively different.
That is, in the time of initiatively, in case fluid flows in the oil cylinder by certain pressure, piston moves back and forth with regard to the limit, and the plane of inclination of edge swash plate rotates sliding freely, and the torque that produce this moment is exported by running shaft, by rotating power is supplied with the device that needs torque, can be used as the oil hydraulic motor utilization.
Otherwise when passive, to the running shaft input torque, piston to-and-fro motion on one side is drawn into the outside with in-oil cylinder fluid on one side, becomes oil hydraulic pump.
This tilted variable axial piston device is widely used in excavator, forklift, bulldozer, hoist and other heavy equipment or various industrial field.
This term of piston apparatus of this specification definition as mentioned above, contains the meaning that two functions are united two into one.Promptly comprise by the moving device of extracting fluid out or producing rotating power by piston motion of pump pumping.
Generally, in ramp type oil hydraulic pump (or compressor) and motor, because the rotation of cylinder tube and piston apparatus assemblying body, swash plate must make piston do oscillating motion in certain angle at rotation prevention state, so in order to prevent the rotation of swash plate, the pivot form that connects transaxle at the central part of swash plate is arranged, has swash plate and following both sides thereof to put into semicylindrical Bracket Type or the like, consider to have complicated structure from the viewpoint of its processability and miniaturization.
With traditional swing ramp type positive displacement compressor is example, proposed patent application Japan is real to open clear 62-183082 number and Korean Patent Publication No. 1996-14656 number and Korean Patent Publication No. 1999-6228 number as being recorded in.The real compressor of opening clear 62-183082 number of above-mentioned Japan, be to rotate the driving body fore-and-aft direction with connecting pin to be connected with the chimeric swivel bearing body that is fixed on the running shaft obliquely, support the swing swash plate with this rotation driving body, by mutual piston rod in a plurality of oil cylinders, be converted to the to-and-fro motion of piston with rotating rotatablely moving of driving body to be connected between a plurality of pistons of decide spaced and parallel insertion and the described swing swash plate.
In addition, on described swivel bearing body, be formed with the slotted hole that guides connecting pin sliding freely, allow the tilting action of described rotation driving body and swing swash plate, keep indefinite substantially top clearance when finishing for compression stroke at piston, even the tilt angle varied of swing swash plate, its upper dead center position can be in the fore-and-aft direction displacement yet.
In addition, the disclosed oil hydraulic pump of Korean Patent, its piston stretches out, directly contact plane of inclination or swash plate is clipped under the state of inner face in its extending area, by carrying out sliding movement and rotatablely moving simultaneously, will rotatablely move is converted to straight line motion, makes piston reciprocates.
Working principle about the tilted variable axial piston device that uses in recent years further describes as follows with reference to Fig. 1-Fig. 4.
At first, structure shown in Figure 1 is that the piston 53 in the cylinder tube 50 moves back and forth along the axial direction of running shaft 40, and the lateral force of utilizing piston 53 simultaneously is to cylinder tube 50 transmitting rotary power.
Promptly, order according to transmission of power, at first when conduct produces the motor function of torque, in case the fluid from the fluid inflow entrance 62 in the liquid flow path assembly 60 flows into oil cylinder, piston 53 promptly moves back and forth, simultaneously sliding sleeve retainer assemblying body 80 is along the plane of inclination rotation of swash plate 72, its rotation produce side force cylinder component 50 rotate simultaneously, and driven rotary axle 40 rotates.
When using as the oil hydraulic pump of extracting fluid out, its power transmission process is, in case the free end of power input running shaft 40, the cylinder component 50 that is connected with the spline 42 of running shaft 40 promptly rotates, driving the sliding sleeve retainer assemblying body 80 that combines with the free end of piston 53 in the oil cylinder 51 rotates along the plane of inclination of swash plate 70, piston 53 is reciprocating simultaneously, and the fluid in the oil cylinder 51 is extracted out.
Above-mentioned traditional tilted variable axial piston device is when cylinder component rotates, and sliding sleeve retainer assemblying body 80 slides along the sphere 41a that is combined in the spheroid 41 on the running shaft 40 and rotates, and utilizes the side force of cylinder component and piston to carry out transmission of power.
The piston 53 of this kind structure can produce violent friction with the cylinder diameter inner face of cylinder tube 50, and this friction can hinder the to-and-fro motion of piston 53, not only reduces mechanical efficiency but also causes generating heat and the too early wearing and tearing of part.
For eliminate this class problem as far as possible, once with the integral body of cylinder tube 50 with copper (
Cu) blank makes, or insert sleeve made of copper at the cylinder diameter inner face, but exist manufacturing process to increase and the big problem of economic burden.
In addition, as shown in Figure 3, when swinging after the combination of piston 53 and sliding sleeve 81, the tilt angle size of swash plate 70 is limited in sliding sleeve 81 and can does in the scope of oscillating motion, and the improvement at tilt angle is restricted, and its scope is about below 14 °.
And the tilt angle of increasing swash plate 70 even just mean that the piston volume 53 of oil hydraulic pump or oil hydraulic motor is constant, also can prolong the stroke of piston 53.
, in case the tilt angle of swash plate 70 surpasses 14 °, piston 53 from the rotation angle just increase of body spherical axis 53a with 81 of sliding sleeves, piston 53 is converted to diagonal movement from straight line motion, sharp wear or damage can take place in the surface that contacts with oil cylinder 51 at piston 53.
As a result, cause the life-span of oil cylinder 51 and piston 53 sharply to shorten, make that the angle design of swash plate 70 is restricted, and the rotation angle of the spherical axis of sliding sleeve and piston 53 directly influences the to-and-fro motion of piston 53.
Therefore, if can regulate the rotation angle from body spherical axis 53a of the piston 53 that combines with sliding sleeve 81 in a wider context, then piston 53 can be reciprocating abreast along the axial direction of oil cylinder 51, therefore can prevent the wearing and tearing of oil cylinder 51 and piston 53 to greatest extent, in addition owing to can be tilt angle greater than in the past, can obtain prolonging the effect of the stroke of piston 53 with the angular adjustment of swash plate 70.As oil hydraulic pump the time, can improve the suction flow of piston 53, during as motor, can strengthen its torque.
For eliminating such problem, maximum solution problem is to avoid the angle of inclination of swash plate 70 to influence to-and-fro motion and the spherical axis 53a of running length and piston apparatus and the rotation angle of sliding sleeve 81 of piston 53.
The result, require power transmitting deice when increasing the angle of described swash plate 70 or dress friction board 72 thereon, can not influence the to-and-fro motion of piston 53, cooperate the position of the sliding sleeve 81 that continues change location along the plane of inclination of swash plate 70 simultaneously again and transferring power fully.
Summary of the invention
The present invention is in order to address the above problem, purpose is to provide a kind of tilted variable axial piston device of universal shaft coupling mode, for prolonging the length of piston apparatus stroke, the tilt angle of its swash plate is than traditional significantly increase, because the tilt angle of this swash plate increases, make and keep parallel along the axis of oil cylinder with the to-and-fro motion of the piston apparatus of sliding sleeve interlock, thereby may wear to minimum with what mechanical friction caused, when the transmission of power that is rotated between axle and sliding sleeve, while change transferring power according to the position of the sliding sleeve that rotates along swash plate.
Another purpose of the present invention is to provide a kind of tilted variable axial piston device, when utilizing universal shaft coupling that torque conversion is converted to torque for straight line motion or with straight line motion, universal shaft coupling is flexible and changeable to be connected with the transmission medium that transmit this power, make the transmission of power unrestricted, thus the tilt angle that can increase swash plate.
A further object of the present invention is to provide a kind of tilted variable axial piston device, transmit by utilizing universal shaft coupling to adapt to different dynamic, the tilt angle of swash plate can freely be increased, thereby can prolong the running length of piston apparatus, improve the suction flow of piston apparatus, the torque that improves rotary driving axles at different levels.
In order to realize the object of the invention, the tilted variable axial piston device of the 1st example is provided with: the bearing unit that the running shaft that has spline on axis is supported, the housing of forming by fluid flowing path assembly with fluid inflow entrance and fluid discharge outlet and inner cylinder with cavity
Be fixedly installed on the interior face of described bearing unit, have swash plate with the plane of inclination of predetermined angular inclination,
Have each fluid passage that optionally is communicated with and the cylinder tube that a plurality of oil cylinders are arranged with described fluid inflow entrance or fluid discharge outlet,
Be installed in the spring on the running shaft of described cylinder tube inside,
Comprise be combined in sliding freely on the swash plate and be located at described in-oil cylinder each piston sliding freely rotate the sliding sleeve retainer assemblying body of a plurality of sliding sleeves that combine freely from the body running shaft,
It is characterized in that, in order to keep transferring power between support body and the described running shaft at described sliding sleeve, on described running shaft, be combined with along the universal shaft coupling of the circumferencial direction rotation of described running shaft, this universal shaft coupling is combined with along the circumferencial direction of described extending portion in each end of the extending portion that extends along three directions and rotates freely, and rotate freely outer race relative to axial direction, inner face at described sliding sleeve retainer assemblying body forms the shaft coupling knothole that inserts for described universal shaft coupling, the surface of described outer race is connected sliding freely with the shaft coupling knothole, and the change in location of corresponding described sliding sleeve is done sliding motion.
The 1st example of the present invention is when making the sliding sleeve retainer assemblying body rotation with a plurality of sliding sleeves by the running shaft that is fixed with swash plate, the universal shaft coupling that on described running shaft, rotates in conjunction with circumferencial direction along this running shaft, this universal shaft coupling has in the extending portion end to three direction branches along extending portion circumferencial direction rotation freely and the outer race that can rotate relative to axial direction, can not separate therefrom and sliding freely with the swash plate surface binding, form the shaft coupling knothole that inserts for described universal shaft coupling on the sliding sleeve retainer assemblying body.
In described the 1st example, with universal shaft coupling to the end of the extending portion of three direction branches form with respect to the axis of extending portion and rotation along the circumferential direction freely and relative to joint that its axial direction rotates, by the outer race that is combined on this extending portion is contacted with sliding sleeve retainer assemblying body, Yi Bian outer race just can be in sliding sleeve one edge swash plate slides the process of rotating the cooperation sliding sleeve change in location and rotate transferring power.
Therefore, though the position change of sliding sleeve, also transferring power mutually between sliding sleeve and universal shaft coupling.Like this, even increase the tilt angle of swash plate, sliding sleeve is also rotatable.In addition, the displacement distance of sliding sleeve can be 14 °~30 ° with the plane of inclination increase of swash plate.The optimal example of the present invention is 20 °.
Have again, for not elongated as traditional because of the sliding sleeve stroke, the straight line motion from the body running shaft of piston apparatus moves along oblique line directions, between sliding sleeve and piston apparatus, be connected piston rod with other rotation joint freely, so can not influence the piston apparatus to-and-fro motion, can do suction action and spinning movement.
The result does straight reciprocating motion and produces rotating power under the state that does not have lateral forces eyeball piston, owing to do not utilize the lateral force of piston, can shorten the length of piston, although shorten, but be connected with sliding sleeve by piston rod, the angle that sliding sleeve can be swung increases to 20 °, so not only can improve the output of oil hydraulic pump or motor with bigger piston stroke, and the friction that causes of the lateral force that can avoid piston, so can increase mechanical efficiency.
The 2nd enforcement of the present invention is to fixedly install universal shaft coupling at swash plate in the tilted variable axial piston device that running shaft rotates, this universal shaft coupling has the circumferencial direction rotation along described running shaft, and along its circumferencial direction rotation freely and the outer race that rotates relative to its axial direction to the end of the extending portion of three direction branches, and formation is inserted for described universal shaft coupling on swash plate, shaft coupling knothole three directions formation, this swash plate is rotated freely along the circumferencial direction of described running shaft, the cylinder component that will comprise a plurality of oil cylinders simultaneously is fixedly installed in the housing, makes the edge slip of the free end of pistons reciprocating in described oil cylinder around swash plate.
During with described the 2nd example, around the edge of this swash plate, during the running shaft rotation, universal shaft coupling makes the swash plate rotation sliding freely, at the same time in Xuan Zhuan the oil cylinder, and piston reciprocates, the load of generation when reducing the swash plate rotation thus.
Therefore, even increase the angle of swash plate, the transmission of power between running shaft and swash plate is also undertaken by universal shaft coupling, not only loads considerably less but also can increase the swash plate angle, improves the suction flow of piston and the torque of running shaft.
That is, when making the running shaft rotation in order to make pump or motor operations at first or making the piston apparatus action, the big more load in the tilt angle of swash plate is big more, and the present invention comes transferring power by the slip between swash plate and the outer race, so load is very little.
Description of drawings
Fig. 1 is the longitudinal sectional view of the internal structure of the traditional axial deflection ramp type axial piston unit of expression.
Fig. 2 is the sectional view of the traditional axial deflection ramp type axial piston unit of expression.
Fig. 3 is the sectional view of the piston apparatus lateral forces in the traditional axial deflection ramp type axial piston unit of expression.
Fig. 4 is the sectional view at the main position of circulation of fluid process when representing traditional axial deflection ramp type axial piston unit work.
Fig. 5 is the longitudinal sectional view of the internal structure of expression tilted variable axial piston device of the present invention.
Fig. 6 is the sectional view of expression by universal shaft coupling of the present invention form of transferring power between running shaft and sliding sleeve retainer assemblying body.
Fig. 7 is the stereogram of sliding sleeve retainer assemblying body of the present invention.
Fig. 8 a is the sectional view that self has the piston apparatus of spherical axis, and b is the sectional view with piston apparatus example of spherical bearing.
Fig. 9 is the sectional view that is rotatably connected to the piston rod between sliding sleeve and the piston apparatus of the present invention.
Figure 10 is the sectional view of universal shaft coupling of the present invention.
Figure 11 is the sectional view of the assembled state of expression universal shaft coupling of the present invention and sliding sleeve retainer assemblying body.
Figure 12 is the main position sectional view that the sliding sleeve of expression variable position of the present invention reaches the stroke of the piston rod that is communicated with it.
Embodiment
Below the best example of present invention will be described in detail with reference to the accompanying tilted variable axial piston device.
Fig. 5 is the longitudinal sectional view of the internal structure of expression tilted variable axial piston device of the present invention, the part mark identical symbol identical with traditional structural element.
Among Fig. 5, the housing of symbol 20 expression tilted variable axial piston devices.
Housing 20 comprises: running shaft 40 is made the bearing unit 30 of axle supporting, the cylinder tube 50 that rotates simultaneously with described running shaft, the fluid flowing path assembly of being made up of the multichannel pipe that flows into or discharge the oil cylinder 51 of described cylinder tube 50 for fluid 60, had the cylindrical body 10 that inside is provided with the cylindrical cavity 10a of described cylinder tube 50.
Described running shaft 40 rotates by bearing 31,61 respectively and is provided in freely on bearing unit 30 and the fluid flowing path assembly 60, and forms spline 42 in the zone of regulation.In the inboard of bearing unit 30, fixing swash plate 70 with fixed pin 32.The surface of swash plate 70 is provided with the friction board of making of superhard alloy 72, and this friction board 72 has 20 ° plane of inclination 71.
In addition, at the central part of described running shaft 40, be equipped with a plurality of sliding sleeves 81 that slide freely on described plane of inclination, preferably 9 sliding sleeves 81 separate the assemblying body of certain arranged spaced.Each described sliding sleeve retainer assemblying body 80 is as Fig. 7 and shown in Figure 11, inside is contained and is branched off into leg-of-mutton shaft coupling knothole 82, and as shown in Figure 5, is provided on the friction board 72 of swash plate 70, be coated with annular pressing plate 73 at an upper portion thereof, described annular pressing plate 73 usefulness bolton are on swash plate 70.
Described annular pressing plate 73 described sliding sleeve retainer assemblying body 80 along described plane of inclination during 71 rotations for guaranteeing the turning radius channeling conduct that it is concentric and making it and can not separate.
Described cylinder tube 50 as shown in Figure 4, inside comprises each oil cylinder 51 with the fluid passage 52 that is communicated with the fluid inflow entrance 62 and the fluid discharge outlet 63 of described fluid flowing path assembly 60, inserts the pistons 53 that slide freely in this oil cylinder 51.The parallel axes of described oil cylinder 51.Cylinder tube 50 combines with described spline 42, can slide freely along the axial direction of running shaft 40, and as long as do not rotate just not can be along the circumferencial direction rotation of running shaft 40 for running shaft 40.And pressure spring 54 is housed in cylinder tube 50 inside, to act on form on the fluid flowing path assembly 60 to cylinder tube 50 application of forces.
Described piston 53 also can have integrally formed spherical axis 53a at its free end shown in Fig. 8 a, also can be shown in Fig. 8 b, have spherical spherical bearing 53b at the inner face of central part.In power transmitting deice of the present invention, more than the piston 53 of two kinds of forms all can adopt.Below further describe its effect example
Described spherical bearing 81a inserts rotating of described piston 53 after body spherical axis 53a goes up, perhaps be located at the free-ended spherical bearing 53b of piston 53 and the spherical bearing 81a of described sliding sleeve 81 and be connected to each other by piston rod 83.Nature, insert in described each spherical bearing 53b, 81a at the two end part of described piston rod 83, and have spherical axis 83a, the 83b that freely rotates.And on the spherical bearing 81a of described sliding sleeve 81, forming fine channel 85, this fine channel 85 connects the face that contacts with the friction board 72 of swash plate 70, flows into for lubricant oil.
Described piston rod 83 has the length of defined, and is provided with the fine channel 84 that connects along its length.The interior pressure that produces during piston 53 to-and-fro motion makes flow of lubricant thread road 84 in a subtle way, will drop to minimum by the mechanical friction that each sliding sleeve 81 and friction board 72 produce.
Universal shaft coupling is to be used for straight line motion is converted to the medium that rotatablely moves, promptly, in case in being forced to property of the fluid inflow oil cylinder 51, piston 53 is just reciprocating, the torque that sliding sleeve 81 is produced when the friction board 72 of swash plate 70 rotates while sliding makes passs running shaft 40, or be used for being converted to straight-line medium with rotatablely moving, promptly, to give sliding sleeve 81 with piston 53 and piston rod 83 interlocks by the transmission of torque that the outside inputs to running shaft 40, to realize the straight line motion of described piston 53.
Described universal shaft coupling 90 as shown in figure 10, the through hole 91 by central part is securely fixed on the running shaft 40, rotates with running shaft 40 one.And universal shaft coupling 90 has with respect to 91 one-tenth of through holes radiation direction and each extending portion 92 of extending in three directions, is provided with each spherical ball bearing 93 at the end face of this extending portion 92.On described spherical ball bearing 93, in conjunction with centering on these spherical ball bearing 93 rotations outer race 94 freely.This outer race 94 has relative each other smooth slip surface at least.
Therefore, described universal shaft coupling 90 can be along the circumferencial direction rotation of running shaft 40, and can transmit or accept to make the power of sliding sleeve retainer assemblying body 80 along the rotation of the circumferencial direction of described running shaft 40, in addition, bearer ring 94 can an edge extending portion 92 circumferencial direction rotate freely an edge axial direction and rotate, so even with the surface slip of the shaft coupling knothole 82 that contact with described outer race 94 also can be corresponding with it.
That is, spherical ball bearing 93 can rotate outer race 94, so can tilt to angle greater than the tilt angle of swash plate 70 to either direction.The outer surface of outer race 94 is a square shape, and insert in the shaft coupling knothole 82 of sliding sleeve retainer assemblying body 80 an one side.
Therefore, during universal shaft coupling 90 rotations, its torque, promptly, make 80 rotations of sliding sleeve retainer assemblying body along the outer race 94 of the universal shaft coupling 90 of the radiation direction of running shaft 40 rotation, otherwise, its transmission of torque is given described outer race 94 and is made running shaft 40 rotations while the to-and-fro motion of piston 53 makes sliding sleeve retainer assemblying body 80 rotate along swash plate 70.
The present invention's the 2nd example is as Korean Patent Publication No. 1996-14656 number is disclosed, rotate and be connected sliding freely the two sides at the edge of this swash plate 70 simultaneously at running shaft 40 and swash plate 70, swash plate rotation and making under the reciprocating situation of piston apparatus during in running shaft 40 rotation, described swash plate 70 is separated with running shaft 40, by forming on this swash plate, can increase the angle of swash plate for the shaft coupling knothole 82 of universal shaft coupling 90 insertions of the present invention, on described running shaft 40, to set above-mentioned universal shaft coupling 90.
During with the 2nd example, when making the running shaft rotation in order to make pump or machine operation at first or making the piston apparatus action, the big more load in the tilt angle of swash plate increases more, and the present invention comes transferring power by the slip between swash plate and the outer race, thus the load drop to very little.
Therefore, variable swash plate of the present invention or axial piston unit are when cylinder component rotates, and rotate simultaneously with cylinder component 50 by the universal shaft coupling 90 direct transferring power of combination on sliding sleeve retainer assemblying body 80 and the running shaft 40, so can not produce lateral force.
Below, illustrate said structure the present invention's the 1st example tilted variable axial piston device make use-case.
At first, the action as the oil hydraulic pump use of suction streams body and function with the present invention is described.
As Fig. 5-shown in Figure 7, in case from the power of outside, be torque input running shaft 40, running shaft 40 promptly begins rotation.The rotation of running shaft 40 is rotated universal shaft coupling 90 and cylinder tube 50 simultaneously, simultaneously outer race 94 with the state of shaft coupling knothole 82 butts under rotate.
At this moment, described sliding sleeve rotates according to the angle of the plane of inclination of swash plate 70 as shown in figure 12, sliding sleeve 81 as 1., 3. friction board 72 rotations of an edge swash plate 70, on one side near or away from oil cylinder 51, so the slip angle between the slip surface of shaft coupling knothole 82 and outer race 94 can change.
Promptly, sliding sleeve is rotation on swash plate 70, even therefore rotation, even be positioned at that 1. the upper of swash plate 70 is located or the most the nextly 3. locate, the angle that sliding sleeve 81 is close on swash plate 70 can not change, and have only variable in distance with oil cylinder 51, so with the junction surface of outer race 94 can great changes have taken place.
And when the change in location of sliding sleeve 81, while rotate by rotating with the spherical ball bearing 93 of the outer race 94 of sliding sleeve retainer assemblying body 80 butts under the state of butt mutually.
As a result, near the surface of outer race 94, on one side slippage is on one side rotated simultaneously, how the position of sliding sleeve 81 changes all keeps connecting in the effect torque.
Because so rotation of the sliding sleeve retainer assemblying body 80 of rotation, just Figure 12 1.~3. between distance in the occurrence positions variation, while the piston 53 and the piston rod 83 that have from the body running shaft rotate reciprocating.Thereby cylinder tube 50 simultaneously as shown in Figure 4, is communicated with the fluid inflow entrance 62 of fluid flowing path assembly 60 with piston rod 53 rotations of rotation, and fluid flows into oil cylinder 51 rapidly.
At this moment, from piston 53 from oil cylinder 51 when retreating.Promptly as Fig. 4 and shown in Figure 12,3. sliding sleeve 81 on swash plate 70 slides into from 1. position on one side, and the position rotates on one side, this moment, fluid was begun by initial 1. position, the fluid inflow entrance 62 of fluid flowing path assembly 60 and the fluid passage 52 of cylinder tube 50 are communicated with gradually, fluid begins to flow into a plurality of oil cylinders 51, promptly in 4 oil cylinders 51, after between 2. and 3. locating, being communicated with fully, 3. locating into dissengaged positions.At this moment, sliding sleeve arrives the position bottom of swash plate 70, and piston 53 is positioned at lower dead centre.
After, the running shaft 40 of rotation makes cylinder tube 50 rotations continuously, and oil cylinder 51 one side are located from 3. beginning to slide to rotate to 1., be reversed above-mentioned action on one side, cut off with fluid inflow entrance 62, fluid discharge outlet 63 and fluid passage 52 are communicated with, and by the suction action of piston 53 fluid are discharged.
In this process, the piston rod between sliding sleeve 81 and piston 53 is the axis of oil cylinder 51 and reciprocating along oblique line directions relatively.But because the effect in the sphere joint of both sides, himself rotates along with the to-and-fro motion of piston 53, so the slip surface of piston 53 and oil cylinder 51 can not wear and tear during to-and-fro motion.Such action is carried out during being input to running shaft 40 from external impetus.Thereby fluid can be extracted out.
Action effect when below explanation is used the present invention as the oil hydraulic motor that produces rotating power.
In this occasion, in case fluid is forced to inject fluid inflow entrance 62, fluid just flows into the fluid passage 52 of the oil cylinder 51 that is communicated with the fluid inflow entrance of fluid flowing path assembly 60, thus piston 53 is released.When piston 53 retreats, have piston rod 83 or together retreat, rotate while slide along the inclined-plane of swash plate 70 from the spherical axis 53a and the sliding sleeve 81 of the piston apparatus of axon.
At this moment the torque of Chan Shenging is rotated a plurality of sliding sleeves 81 simultaneously, and makes cylinder tube 50 rotations, and sliding sleeve makes described running shaft 40 rotations to the outer race 94 reverse application of forces of universal shaft coupling 90.
Certainly, the cylinder tube 50 of rotation is to carry out continuously the action that is communicated with or cuts off with fluid inflow entrance 62 or fluid discharge outlet 63 selectively simultaneously by its inner fluid passage 52, carries out the inflow and the discharging operation of fluid thus simultaneously.
Thereby, forced fluid flow is gone in the oil cylinder 51, on running shaft 40, produce torque.
As mentioned above, can be used for the tilted variable axial piston device of the present invention of oil hydraulic pump and motor, can extract fluid out, or utilize hydraulic power to produce torque by rotating power.And at the joint portion at the connecting rod two ends of piston 53 because of very frequent friction takes place, in order to prevent this rotary part wearing and tearing, flows into through described fine channel by making lubricant oil, can make weares and teares drops to minimum.
About this point, shown in Figure 8 as Fig. 5, lacking on piston 53 and the connecting rod 83 in conjunction with the spherical ball bearing, on piston 53, form the very little capillary tube stream of diameter, pressure oil that is supported by receiving piston 53 and the oily recess of supplying with the spherical ball bearing, even piston 53 and piston rod 83 are adjacent to motion mutually because of substantial load, also can make friction drop to minimum.
As mentioned above, the present invention can increase traditional piston 53 and the rotational angle range between sliding sleeve that limits the tilt angle of swash plate 70, so piston can be reciprocating along the parallel axes ground of oil cylinder 51, in addition, the angle of swash plate 70 can increase to from traditional 14 ° more than 20 °, can prolong the stroke of the sliding sleeve 81 that rotates while sliding on swash plate, therefore comparable traditional oil hydraulic pump or motor segment have more capacity.
The result, when the tilted variable axial piston device transferring power, because lateral force without piston 53 or piston rod 83, can make and the cylinder diameter inner face of cylinder tube 53 between friction reduce to minimum, needn't sleeve be set at the cylinder diameter inner face and prevent the stuck phenomenon that causes because of lateral force, and because of being provided with the spherical ball bearing in piston rod 82 both sides, so drop to minimum for the mechanical friction of main motive position, mechanical efficiency improves.
Claims (9)
1. tilted variable axial piston device is provided with: the bearing unit that the running shaft that has spline on axis is supported, and the housing of forming by fluid flowing path assembly with fluid inflow entrance and fluid discharge outlet and inner cylinder with cavity,
Be fixedly installed on the interior face of described bearing unit, have swash plate with the plane of inclination of predetermined angular inclination,
Have each fluid passage that optionally is communicated with and the cylinder tube that a plurality of oil cylinders are arranged with described fluid inflow entrance or fluid discharge outlet,
Be installed in the spring on the running shaft of described cylinder tube inside,
Comprise be combined in sliding freely on the swash plate, be located at described in-oil cylinder each piston sliding freely rotate the sliding sleeve retainer assemblying body of a plurality of sliding sleeves that combine freely from the body running shaft,
It is characterized in that, in order to keep transferring power between support body and the described running shaft at described sliding sleeve, on described running shaft, be combined with along the universal shaft coupling of the circumferencial direction rotation of described running shaft, this universal shaft coupling is combined with along the circumferencial direction of described extending portion in each end of the extending portion that extends along three directions and rotates freely, and rotate freely outer race relative to axial direction, inner face at described sliding sleeve retainer assemblying body forms the shaft coupling knothole that inserts for described universal shaft coupling, the surface of described outer race is connected sliding freely with the shaft coupling knothole, and the change in location of corresponding described sliding sleeve is done sliding motion.
2. tilted variable axial piston device as claimed in claim 1 is characterized in that, the free end of described piston rotates and combines with described sliding sleeve freely.
3. tilted variable axial piston device as claimed in claim 2 is characterized in that, the fine channel that on the face that contacts of the spherical bearing inner face of described sliding sleeve and described swash plate, is formed for lubricating, and lubricant oil flows into this fine channel.
4. tilted variable axial piston device as claimed in claim 1, it is characterized in that, during described reciprocating motion of the pistons, can be reciprocating abreast for making piston along the center line of oil cylinder, between described sliding sleeve and piston, be connected with piston rod, and with the combination rotationally of its two end part.
5. tilted variable axial piston device as claimed in claim 4 is characterized in that, at the length direction formation fine channel of described piston rod, lubricant oil flows into the rotary part of described piston and sliding sleeve through this fine channel.
6. tilted variable axial piston device as claimed in claim 1 is characterized in that, the free end of described piston rotates and combines with the sliding sleeve of described sliding sleeve retainer assemblying body freely.
7. tilted variable axial piston device as claimed in claim 1 is characterized in that, the outer race of described universal shaft coupling can be around the rotational of extending portion.
8. tilted variable axial piston device is provided with: the bearing unit that the running shaft that has spline on axis is supported, and the housing of forming by fluid flowing path assembly with fluid inflow entrance and fluid discharge outlet and inner cylinder with cavity,
Rotate the swash plate that is combined into one with described running shaft freely and has the plane of inclination of regulation,
Have each fluid passage that optionally is communicated with and the cylinder tube that a plurality of oil cylinders are arranged with described fluid inflow entrance or fluid discharge outlet,
Be installed in the spring on the running shaft of described cylinder tube inside,
Combine with the edge surface of described swash plate sliding freely and sliding freely with described oil cylinder in each piston of combining,
It is characterized in that, make described running shaft separate rotation with swash plate for transferring power between described swash plate and described running shaft, have on described running shaft by the cylindrical direction rotation, by in the end of the extending portion of three direction branches along the freely and relative universal shaft coupling that constitutes of the rotating outer race of its axis of the circumferencial direction rotation of its axis
The swash plate rotation that will have the shaft coupling knothole that inserts for described universal shaft coupling is combined on the described running shaft freely, by described universal shaft coupling transferring power between described running shaft and swash plate.
9. as claim 1 or 8 described tilted variable axial piston devices, it is characterized in that the tilt angle of described swash plate is 14 °-30 °.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR20010047059 | 2001-08-03 | ||
KR10-2001-0047059A KR100413948B1 (en) | 2001-08-03 | 2001-08-03 | Variable Displacement Type Axial Piston Unit |
Publications (2)
Publication Number | Publication Date |
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CN1407256A true CN1407256A (en) | 2003-04-02 |
CN100406724C CN100406724C (en) | 2008-07-30 |
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Application Number | Title | Priority Date | Filing Date |
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CNB011429666A Expired - Fee Related CN100406724C (en) | 2001-08-03 | 2001-12-03 | Tilted variable axial piston device |
Country Status (3)
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JP (1) | JP2003113776A (en) |
KR (1) | KR100413948B1 (en) |
CN (1) | CN100406724C (en) |
Cited By (7)
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CN105114278A (en) * | 2015-07-24 | 2015-12-02 | 杭州绿聚科技有限公司 | Novel axial plunger pump |
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KR20040094123A (en) * | 2003-05-01 | 2004-11-09 | 라필찬 | universal pump |
KR100773988B1 (en) * | 2006-06-30 | 2007-11-08 | 동명모트롤 주식회사 | Swashplate structure of swashplate type axial piston hydraulic pump |
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CN105090008B (en) * | 2015-07-24 | 2017-08-01 | 杭州绿聚科技有限公司 | Axial plunger pump |
WO2017169552A1 (en) * | 2016-03-28 | 2017-10-05 | 株式会社神戸製鋼所 | Hydraulic rotary machine |
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CN1003382B (en) * | 1985-04-01 | 1989-02-22 | 上海交通大学 | Binary digital control oblique tray type axial plunger piston variable pump |
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JPH1037848A (en) * | 1996-07-25 | 1998-02-13 | Tokimec Inc | Axial piston type hydraulic device |
JP2000230479A (en) * | 1999-02-09 | 2000-08-22 | Nippon Soken Inc | Swash type variable capacity compressor |
JP2000283028A (en) * | 1999-03-26 | 2000-10-10 | Toyota Autom Loom Works Ltd | Variable displacement type compressor |
CN2409350Y (en) * | 1999-12-28 | 2000-12-06 | 马剑 | Piston rod volume variable displacement regulator |
-
2001
- 2001-08-03 KR KR10-2001-0047059A patent/KR100413948B1/en active IP Right Grant
- 2001-12-03 CN CNB011429666A patent/CN100406724C/en not_active Expired - Fee Related
-
2002
- 2002-01-23 JP JP2002014871A patent/JP2003113776A/en not_active Withdrawn
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Also Published As
Publication number | Publication date |
---|---|
KR100413948B1 (en) | 2004-01-07 |
JP2003113776A (en) | 2003-04-18 |
CN100406724C (en) | 2008-07-30 |
KR20030012685A (en) | 2003-02-12 |
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